With the development of the mobile network, mobile videophone services also become increasingly popular. The mobile videophone services provide on a wireless network multimedia communication services of any combination of media formats such as real-time video, audio, or data, and mainly utilize the wireless network to implement a video call on a mobile device, thereby enabling mobile users to perform interaction of real-time audio, video, and the like, at any place in any time, that is, both parties of the call can see the other party during the conversation.
The videophone services can be implemented in a packet mode or a circuit mode. However, as the 3G network becomes increasingly mature, the videophone services generally refer to videophone services implemented based on a circuit-switched (CS) domain bearer of Wideband Code Division Multiple Access (WCDMA) or Time Division-Synchronous Code Division Multiple Access (TD-SCDMA). The routing rule of the 3G video call is to, after a call is initiated, record a call type (for example, whether it is a video play (VP) call) through bearer capability, analyze a called number, and obtain information of the call such as the service class, service attribute, and type of the called number. The VP may be regarded as a characteristic of the call. Calling characteristic analysis is performed on calls with such characteristic, and a desired routing mode and a desired routing direction are decided according to a result of the analysis.
However, in the existing videophone services, media negotiation and establishment of a media channel of the video call are directly implemented by both calling and called terminals. Thus, during the video call, the calling and called parties can only see the contents shot by the other party's camera but cannot see other contents. As a result, the user's experience is greatly degraded and the demand of the diversity of the existing videophone services cannot be met.